Cutter bar, cutter chain and sprocket assembly

ABSTRACT

A cutter bar, cutter chain and sprocket assembly wherein means are provided to maintain the pintles joining the chain links in spaced relationship to and beyond the chain guide surfaces on the peripheral edges of the cutter bar. The ends of the pintles are free to extend beyond the exterior surfaces of the links they join, although they do not necessarily have to be so arranged. The pintles are preferably freely rotatable and means may be provided at their ends to hold the pintles in place with respect to the links they join. The pintles are so located and the link so configured that the line of force passing through the pintles also passes through body portions of the links which support cutter bits so that the distance between this line of force and the points of contact between the cutter bits and the material being mined is greatly reduced.

United States Patent [72] inventor Claude B. Krekeler Cincinnati, Ohio1211 Appl. No. 844,551 {22] Filed July 24, 1969 [45] Patented Sept. 14,1971 [73] Assignee The Cincinnati Mine Machinery Co. Cincinnati, Ohio[54] CUTTER BAR, CUTTER CHAIN AND SPROCKET ASSEMBLY 46 Claims, 20Drawing Figs. [52] US. Cl 299/84, 74/229, 74/250, 143/32 [51] Int. Cl..E2lc 25/30, E210 25/34 [50] Field of Search 299/82, 83, 84;74/229,250; 143/32 [56] References Cited UNITED STATES PATENTS 1,239,3849/1917 Gisch 143/32 1,349,557 8/1920 Boswell 143/32 2,418,199 4/1947Simmons 74/250 Primary Examiner-Emest R. Purser Attorney-Melville,Strasser, Foster & Hoffman ABSTRACT: A cutter bar, cutter chain andsprocket assembly wherein means are provided to maintain the pintlesjoining the chain links in spaced relationship to and beyond the chainguide surfaces on the peripheral edges of the cutter bar. The ends ofthe pintles are free to extend beyond the exterior surfaces of the linksthey join, although they do not necessarily have to be so arranged. Thepintles are preferably freely rotatable and means may be provided attheir ends to hold the pintles in place with respect to the links theyjoin. The pintles are so located and the link so configured that theline of force passing through the pintles also passes through bodyportions of the links which support cutter bits so that the distancebetween this line of force and the points of contact between the cutterbits and the material being mined is greatly reduced.

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ATTOR N EYS CUTTER BAR, CUTTER CHAIN AND SPROCKET ASSEMBLY BACKGROUND OFTHE INVENTION 1. Field of the invention The invention relates to acutter bar, cutter chain and sprocket assembly for mining machines andthe like, and more particularly to improvements in the individual partsthereof.

2. Description of the Prior Art Prior art workers have made extensiveuse of cutter bars as, for example, in undercutting a seam of materialto be mined, preparatory to loosening a portion of the material byblasting. Cutter bars have taken various forms depending upon the use towhich they have been put. In some instances, for example, a cutter baris rigidly mounted on a mining machine so that the machine itself mustbe moved in order to move the cutter bar. In other instances, a cutterbar is pivotally mounted to a mining machine so that it may be traversedin the direction of the out.

In general, a cutter bar comprises an elongated element having a cutterchain passing about its peripheral portions and driven by the miningmachine to which the cutter bar is affixed. In its usual form, thecutter bar is so constructed as to have a peripheral channel orpassageway in which the cutter chain rides. For example, in its mosttypical form, a cutter bar comprises a pair of parallel spaced beamshaving plate members affixed to the top and bottom surfaces thereof.Edge portions of the plate members define the sidewalls of the cutterchain channel while the beams themselves form the channel bottoms. Theend of the cutter bar is semicircular in configuration so that thechannel is continuous about the periphery of the cutter bar. The sidesand bottom of the cutter bar channel are frequently lined with wearstrips of hardened steel which may be replaced as needed.

Cutter chains have taken many forms. In general, however, a cutter chaincomprises a plurality of link members pivoted together by pintles.Certain of the link members have means for mounting cutter bits. in thenormal cutter chain, there is a plurality of double-link membersproviding spaced cheeks interconnected at the top by blocklike portionsor lugs, which are perforated so as to receive the shanks of cutter bitsor cutter bit holders. Alternate link members are single elements, theends of which lie between the cheeks of the double-link members, thevarious elements being pivoted together by pintle means. The pintlemeans are generally cylindrical elements which pass through perforationsin the cheeks of the doublelink members and perforations in the ends ofthe alternate single-link members.

Cutter bar-cutter chain assemblies of the general type described abovehave been in widespread and successful use for many years. However, theyare characterized by a number of problems and disadvantages. Forexample, since each of the double-link members providing spaced cheekshas its cheeks interconnected at the top by a block or lug for mountinga cutter bit, the point of contact between the cutter bit tip and thematerial being mined lies at a considerable distance from the line offorce on the chain passing through the chain pintles. As a consequence,there is a strong tendency for the lugbearing link members to pivot in adirection opposite to the cutting direction. This, in turn, createsconsiderable vibration and kick in the cutter chain and the assembly asa whole.

The various cutting forces and vibrational strains of the cutter barhave a tendency, in time, to cause the cutter bar channel sidewall tospread apart. This spreading of the channel walls results in additionalvibration of the parts and additional wear thereof. The undesirableeffects created by the spreading of the channel walls is cumulativebecause the cutter bar normally outlasts a number of cutter chains.

Finally, since the cutter chain in prior art structures passes about thecutter bar in a peripheral channel, and since the pintles connecting thechain link members lie within the peripheral channel, the pintles cannothave their ends extend beyond the outside surfaces of the checks of thedoublecheeked link members. As a result, great difficulties have beenencountered in devising means for keeping the pintles in place. Priorart workers have developed many forms of specifically configured pintlestogether with a multitude of keys, clips and other keeping devices. Inmost embodiments the pintles are nonrotatively held either by thesingle-link elements or the double-link elements with the result thatthey were not subject to even wean.

The present invention is directed to improved means for solving thevarious problems outlined above.

SUMMARY OF THE INVENTION The present invention is directed to improvedcutter bar, cutter chain and sprocket assemblies. in general, the cutterbar may comprise an elongated platelike member. The cutter bar issuitable mounted on a mining machine. The forward end of the cutter barhas guide means for the cutter chain. A sprocket is mounted inassociation with the rearward end of the cutter bar to drive the chainabout the peripheral edges thereof.

The present invention contemplates a number of embodiments of cutterchain-cutter bar assemblies. in on embodiment the cutter chain may be ofa type comprising a plurality of link members each having a body portionadapted to mount a cutter bit. The body portion has a single-linkextension at its forward end and a pair of spaced link extensions at itsrearward end. These link extensions are so configured that the forwardextension of one link member is adapted to be received between thespaced link extensions of an adjacent link member. Pintle means passthrough the coaxial perforations in the nested link extensions. Eachlink member has a pair of spaced legs adapted to straddle, and slidablyengage the wear strips on the edges of the cutter bar.

A second type of cutter chain bay be used, differing from the firstprimarily in that those link members having body portions adapted tomount cutter bit means have spaced, doublelink extensions at both ends.These link members are joined, in turn, by single-link members the endsof which are located between the double-link extensions of adjacentcutter-bit-carrying link members. Again, the nested extensions arejointed by pintle means passing through coaxial perforations therein.

In both chain types thus far described, each link member mounting acutter bit means may have a pair of spaced legs adapted to straddle andto slidably engage the peripheral edge portions of the cutter bar. Asindicated above, these edge portions may constitute wear strips. Byvirtue of this construction, the entire cutter chain is exposed to thematerial being mined and will provide a sweeping action for the materialwhich has been cut.

When the cutter-bit-mounting links are provided with spaced pairs oflegs, a sprocket may be provided having a plurality of evenly spacedlateral extensions protruding from both faces thereof and adapted toengage the edges of the spaced legs of each bit-carrying link member soas to drive the chain about the periphery of the cutter bar.

On the other hand, a conventional sprocket may be used with thefirstmentioned type of chain. In such an instance the sprocket teethengage the rear surface of the body portion of each link member betweenthe spaced pair of link extensions thereon.

Whether the link-members-carrying cutter bit means are joined directlytogether as in the first-mentioned type of chain or by means ofsingle-link elements as in the second chain type, eachcutter-bit-carrying link member may be provided with a single leg ofinverted T-shaped cross section. in this instance, the cutter bar has aperipheral channel of inverted T shaped cross section. The legs of thebit-carrying link members are adapted to be slidably engaged in thecutter bar channel. The driving sprocket will be of substantiallyconventional design adapted to engage edge portions of the T-shaped legsand to drive the chain by virtue of this engagement.

In all of the embodiments thus far described, the pintle means arelocated beyond the peripheral edges of the cutter bar. By virtue of thisconstruction, the distance from the point of contact between the cutterbit tip and the material being cut and the line of force passing throughthe pintles is greatly reduced. Similarly, the ends of each pintle mayextend beyond the outside surfaces of the link members it joins.Fastening means may be applied to the pintle ends and the pintles,themselves, may be freely rotatable and thereby subject to even wear.The holes in the link members through which the pintles extend are alsosubject to wear, thereby further distributing the wear.

The assembly of the present invention is far simpler in construction andless expensive to manufacture than prior art structures. The individualparts are subject to less vibration, kick and wear, and are caused towear more evenly.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary plan viewillustrating one embodiment of a cutter bar, cutter chain and sprocketassembly of the present invention.

FIG. 2 is a fragmentary side elevational view of a cutter chain of thepresent invention.

FIG. 3 is a fragmentary plan view of the cutter chain of FIG. 2.

FIG. 4 is a perspective view illustrating another mode of constructionof the link members of FIGS. 2 and 3.

FIG. 5 is a fragmentary perspective view illustrating one form ofpintle.

FIG. 6 is a plan view of a retaining ring or spring clip for use withthe pintle of FIG. 5.

FIG. 7 is a fragmentary cross-sectional view taken along the sectionline 7-7 of FIG. 1 and showing a cutter bit mounted in the link member.

FIG. 8 is a view similar to FIG. 7 illustrating another form of wearstrip on the cutter bar and another placement of a cutter bit in thelink member.

FIG. 9 is a fragmentary cross-sectional view similar to FIG. 7illustrating a modified form of chain link member similar to that ofFIGS. 2 and 3.

FIG. 10 is a fragmentary perspective view of the forward end of a cutterbar of the present invention.

FIG. 11 is a perspective view illustrating another embodiment of thecutter chain of the present invention.

FIG. 12 is a fragmentary elevational view illustrating anotherembodiment of a cutter chain-cutter bar assembly.

FIG. 13 is a fragmentary cross-sectional view taken along the sectionline 13-13 of FIG. 12.

FIG. 14 is a perspective view of cutter chain link members similar toFIG. 11, but having a single cutter-bar-engaging leg.

FIG. 15 is a fragmentary plan view illustrating a conventional drivesprocket and another embodiment of the cutter chain of the presentinvention.

FIG. 16 is a perspective view of a chain link member of FIG. 15.

FIG. 17 is a plan view of a pair of chain link members illustrating yetanother embodiment of the present invention.

FIGS. 18 and 19 are perspective views of special sprockets which may beused with certain of the chains of this invention.

FIG. 20 is a fragmentary cross-sectional view similar to FIG. 7illustrating a chain link member carrying two cutter bits.

DESCRIPTION OF THE PREFERRED EMBODIMENTS While the present invention isdescribed in terms of a cutter bar assembly for a mining machine of thetype used in undercutting a seam of coal of the like, it will beunderstood by one skilled in the art that it is within the scope of theinvention to apply the principles thereof to any suitable form ofchainbearing mining machine. The mining machine itself and the manner inwhich the cutter bar is affixed to the mining machine are well known inthe art and do not constitute a part of the present invention.

Reference is made to FIG. 1 wherein an embodiment of the assembly of thepresent invention is shown. In FIG. I, the cutter bar is generallyindicated at l, the sprocket is generally indicated at 2 and the cutterchain is generally indicated at 3.

The cutter bar 1 comprises an elongated, substantially rectangularplatelike member 4. The longitudinal edges 5 and 6 of the cutter bar 4may each be provided with a pair of wear strips. Two such wear stripsare shown at 7 and 8 in FIG. I. The wear strips may be made of anysuitable material such as hardened steel and may be fastened to thecutter bar body 4 in any well-known way, inclusive of bolts, rivets andthe like (not shown). The fastening means should be appropriatelycountersunk so that the exterior surfaces of the wear strips areunobstructed. Preferably the wear strips should be affixed to the cutterbar in such a way as to be readily replaceable, although the wear stripsmay constitute integral parts of the cutter bar ifdesired.

FIG. 7 shows an exemplary pair of wear strips 70 and 7b. In thisinstance, the wear strips are of angle iron cross section so as toprotect both the sides and end portion of the longitudinal edge 5 of thecutter bar. The wear strips should be so sized as to have a smallclearance (indicated at 9) to insure that they may be properly locatedon the sides of the cutter bar body. It will be understood by oneskilled in the art that the wear strips 7a and 7b could be an integral,one-piece structure of channelshaped cross section, as illustrated at 7cand 8c in FIG. 10.

FIG. 8 illustrates an alternate form of wear strip. In this instance,the wear strips 7d and 7e comprise elongated members of rectangularcross section, affixed to the sides of the cutter bar body adjacent thelongitudinal edge 5.

Referring again to FIG. I, the sprocket 2 is mounted on the miningmachine at the rearward end of the cutter bar 1. The manner in which thecutter bar and the sprocket are mounted on the mining machine is notshown. These mountings may be conventional, and do not constitute a partof the present invention.

The sprocket comprises the means by which the chain 3 is driven aboutthe peripheral edges of the cutter bar 1. The sprocket comprises adisclike element having a plurality of transverse extensions 10 spacedabout its periphery. The extensions l0 protrude from both faces of thedisclike element so that they will engage both legs of the cutter chainlink members (as will be described hereinafter).

The body of the sprocket 2 should have a transverse thicknessapproximately equal to the thickness of the cutter bar body 4. Theextensions 10 should be so sized as to enable them to engage the legs ofthe cutter chain elements. The extensions 10 may be integral portions ofthe sprocket body, elements affixed to either face of the sprocket bodyor elements affixed in notches in the sprocket body. The peripheralportion of the sprocket may have any suitable configuration. Forexample, it may be circular as illustrated in FIG. 1, or it may berelieved (as shown by the dotted line 11) so as to have a scallopedconfiguration.

FIGS. 2, 3 and 7 illustrate one embodiment of the cutter chain of thepresent invention. The cutter chain is made up of a plurality ofsubstantially identical link members. One such link member is generallyindicated at 12 in FIGS. 2, 3 and 7. The link member comprises a bodyportion 13 having a single forward link extension 14 and a pair ofspaced rearward link extensions 15 and 16. It will be noted that theforward link extension 14 and the rearward link extensions 15 and 16 arein line with the body 13.

The forward link extension 14 has a transverse perforation 17. Therearward link extensions 15 and 16 have coaxial transverse perforationsl8 and 19, respectively.

The body 13 has a bottom surface 20 which may be planar if the sprocket2 has a noncircular peripheral configuration. When the sprocket 2 has acircular peripheral configuration, the central portion of the bottomsurface 20 may have an arcuate relief (as shown in FIGS. 1, 2 and 7) soas to conform to the sprocket edge. When the arcuate relief extends thefull width of the bottom surface 20, the link member will ride on bottomsurface portions 20a and 20b (FIG. 2) when in straight travel. If therelief is of a width substantially equal to the thickness of thesprocket body, shoulders 20c and 20d (FIG. 7) will be formed extendingthe length of the bottom surface of the link member and comprisingbearing surfaces when the link member travels along the straight,longitudinal edges of the cutter bar.

The chain link body l3 also has a pair of spaced legs 21 and 22extending therefrom. As shown in FIG. 7, the distance between the legs21 and 22 is such as to permit a sliding fit of the cutter bar and wearstrips therebetween. The legs 21 and 22 have inwardly directedextensions 23 and 24, respectively, so as to render the link membercaptively mounted on the cutter bar by virtue of the interaction betweenthe extension 23 and the wear strip 7b and the extension 24 and the wearstrip 7a.

The forward and rearward edges of the legs 21 and 22 are relieved.Reliefs 25 and 26 on leg 22 are illustrated in FIG. 2. The leg 21 (notshown in FIG. 2) will be relieved in an identical manner.

The purpose of the relief is clearly shown in FIG. I. The reliefs are soangled as to serve as engagement surfaces for the sprocket extensions 10whereby the extensions can engage and drive the link members about thecutter bar. It will be understood by one skilled in the art that thereliefs on those link member legs on the other side of the sprocket willsimilarly be engaged by sprocket extensions 10 on that side of thesprocket.

In FIG. 8, the link body 13 is substantially identical to that of FIG. 7and is provided with identical legs having the same index numerals. Theinteraction of the extended leg portions 23 and 24 and the wear strips7e and 7d is the same. The only difference between the embodiment ofFIG. 8 and that of FIG. 7 is the fact that the bottom surface of thebody 13 rides directly on the edge 5 of the cutter bar body 4 and theoutermost edges of the wear strips 7d and 7e.

In FIGS. 2 and 3, adjacent link members are fragmentarily illustrated at12a and 12b. These link members are substantially identical to the linkmember 12 and like parts have been given like index numerals followed bya and b, respectively. As will be evident from FIGS. 2 and 3, theforward link extensions 14 of the link 12 will nest between the spacedrearward link extensions 15a and 16a of link member 12a. Theperforations 17, 18a and 19a of the link extensions 17, 15a and 16a,respectively, will be coaxial and will accept a cylindrical pintle 27.

Similarly, the link extension 14b of link member 12b will nest betweenthe rearward link extensions 15 and 116 of link member 12. Theperforations 17b, 18 and 19 in link extensions 14b, 15 and 16respectively, will be coaxial and will accept a cylindrical pintle 28.In this way, adjacent link members may be joined to form an endlesscutter chain.

Since the pintle-carrying link extensions are affixed directly to thebody portions of the chain link members and since the pintles do notride in a continuous channel on the cutter bar, the ends of the pintles27 and 23 may extend beyond the exterior surfaces of link extensions15zz-l6a and 15-16, respectively. This in turn, enables the use offastening means at the ends of the pintles. Thus, the pintles may have adiameter such as to be freely rotatable in the perforations in the linkextensions, resulting in even wear of the pintles and far longer pintlelife.

Any suitable means may be used to hold the pintles in their properplace. For example, pintle 27 in FIG. 2 is illustrated as having a nut29 threaded thereon. Pintle 28 in FIG. 2 is illustrated as having atransverse perforation 28a adapted to receive a roll pin 30.

In FIG. 3, pintle 27 is illustrated as having a head 31 at one end, anda roll pin 32 at the other. Pintle 28 is illustrated as being held inplace by spring clips or retaining means 33 at both ends.

The latter arrangement is more clearly illustrated in FIGS. 5 and 6. Asshown, the pintle 28 is provided near its end with an annular groove 34.The annular groove is adapted to receive the retaining ring or springclip 33 of FIG. 6. The outside diameter of the ring 33 is greater thanthe diameter of the pintle and the diameter of the perforations throughwhich the pintle extends. The inside diameter of the ring 33 is lessthan the diameter of the pintle and substantially equivalent to thediameter of the groove or notch 34. The ring 33 is split so as to forman opening between its ends. The width of the opening is less than thediameter of the notch or groove 34. The retaining ring will be made ofresilient metal or the like and can be forced into position in thegroove 34.

From the above it will be evident to one skilled in the art that thepintles 27 and 28 may be provided with any of the above describedretaining means, or any combination of them.

The spaced rearward link extensions of each chain element may beprovided with rearwardly facing planar surfaces. Such surfaces areillustrated at 34 and 35 on link extensions 15 and 16, respectively, andat 34a and 35a on link extensions 15a and l7a, respectively. The forwardend of the link element 12 may be provided with planar surfaces 36 and37 on either side of the link extensions 14. Similarly, the link elementll2b may be provided with planar surfaces 36b and 37b on either side oflink extension 14b. When the cutter is passing through its straightflights on either side of the cutter bar I, the planar surface 34-35 and3411-3511 on the rearward link extensions will coact with the planarforward surfaces 36b-37b and 36-37, respectively, to rigidify the cutterchain. It is also within the scope of the invention to configure aportion of the forward surfaces 3637 or 36b-37b as shown in FIG. 1 at37c and 37d. This configuration aids in the prevention of theaccumulation of fines and foreign materials between the rearward link extensions of one chain element and the forward faces of the adjacentchain element.

The type of cutter bit or cutter bit adapter carried by the body I3 doesnot constitute a limitation on the present invention. For purposes of anexemplary showing, the body 13 is illustrated in FIGS. 2, 7 ans 8 ascarrying a cutter bit of the general type set forth in U.S. Pat. No. 3,]14,537. It will be understood, however, that other types of cutter bitsor cutter bit adapter assemblies may be used. For example, the linkmembers may be adapted to mount the pick-type conical cutter bits, inextensive use today, and exemplified by U.S. Pat. Nos. 3,397,012 and3,397,013. Similarly, nonrotatable cutter bits made from round stock maybe used. Such cutter bits are taught in the copending applicationentitled CUTTER BITS AND MEANS FOR MOUNTING THEM, Ser. No. 753,398,filed Aug. 19, 1968 in the name of the same inventor.

For purposes of an exemplary illustration, the body 13 is shown ashaving a shank-receiving perforation 38 and a transverse hole 39partially intersecting the shank-receiving perforation. The transversehole 39 is adapted to receive a resilient retaining means, which may beof the type described in the above-mentioned U.S. Pat. No. 3,114,537.The retaining means comprises a pin 40, at least the ends of which aresurrounded in bodies of resilient material 41. The retainer may have alongitudinal key 42 and the transverse hole 49 may have a longitudinalkeyway 43. Interaction of the key 42 and the keyway 43 will maintain theresilient retainer in its proper orientation, with the pin extendingpart way into the shankreceiving perforation 38.

The cutter bit, generally indicated at 44, comprises a head 45 and ashank 46. The head 45 may be provided with a hard cutting tip 450,gauge-determining abutment surfaces 47 and a surface 48 for engagementby a bit removal tool. The shank 46 has a relief 49 at its bottomrearward edge and a substantially hook-shaped notch 50 in its rearsurface. When the shank of the cutter bit is inserted in theshank-receiving perforation 38, the relief surface 49 will cause theretainer pin 40 to move rearwardly and out of the shank-receivingperforation. When the cutter bit is in its fully seated position, theretainer pin 40 will engage the hook-shaped notch 50 in the cutter bitshank to maintain the cutter bit shank in its seated position.

In the usual practice, the cutter bits on the cutter chain are orientedat various angles so that a cut is made of sufficient width to permitpassage of the cutter bar-cutter chain assembly. To accomplish this, thetop surface of the body 13 may be appropriately configured and theshank-receiving perforation 38 and transverse hole 29 may be properlyoriented. In FIG. 7, for example, the cutter bit 44 is shown lying insubstantially the same plane as the cutter bar 1. However, the cutterbit 44 may be oriented anywhere along the dotted arcuate line A. FIG. 8,for example, illustrates the cutter bit 44 lying at an angle of about 45to the transverse axis of the cutter bar 1. The placement of the cutterbit may be varied throughout an arc of about I80". It is also within thescope of the present invention to make the body 13 of the chain elementof such size as to enable it to mount more than one cutter bit atvarying angularities.

FIG. is a perspective view illustrating the forward end of the cutterbar 1. As indicated above, for purposes of an exemplary showing thecutter bar body 4 is illustrated as having wear strips 70 and 8c affixedto its longitudinal edges, the wear strips having a U-shapedcross-sectional configuration. The forwardmost end of the cutter barcomprises a shoe 51, one end of which is affixed to the forward end ofthe cutter bar body 4. The shoe 51 may be affixed to the cutter bar bodyby welding or the like, or it may be removably affixed by bolts or othersuitable means (not shown). On the other hand, the shoe may constitutean integral part of the cutter bar. The forward end of the shoe 51 issubstantially semicircular. The peripheral edges of the shoe areprotected by wear strip means generally indicated at 52. The wear stripmeans 52 may be of any of the types set forth above, and removablyaffixed to the shoe by conventional means. Preferably, however, the wearstrip means 52 comprises an integral portion of the shoe 51. This istrue because the wear strip portion 52 will be subjected to greaterstresses than wear strip means along the longitudinal edges of thecutter bar and, if removably affixed, will have a tendency to be brokenoff in time, during the cutting operation. That portion of the wearstrip means 52, passing about the semicircular edge of the shoe 51 willbe narrower than the straight portion (as illustrated in FIG. 10) topermit the leg extensions 23 and 24 to pass thereabout.

It will be understood by one skilled in the art that it would be withinthe scope of the invention to use a sprocket at the forward end of thecutter bar rather than the shoe 51. For example, the sprocket could beidentical to the one shown in FIG. 1, except that it would be an idlersprocket rather than a driven one. For purposes of the presentdiscussion, FIG. 1 could be considered the forward end of the cutter bar1 with the sprocket 2 rotatively mounted thereto by means not shown.

The operation of the cutter bar, cutter chain and sprocket assembly ofthe present invention will be obvious in view of FIG. 1. If the cutterchain 3 is caused to move in a cutting direction (shown by arrow B), theindividual chain elements will move forwardly along the wear strips 7 onthe cutter bar and will be captively held thereon by the inner action ofthe chain element legs and the wear strips. At the rearward end of thecutter bar 1, the chain elements will pass forwardly to the sprocket 2and the link element legs will straddle the sprocket and be engaged bythe transverse extensions 10. In this manner, the chain elements will bedriven by the sprocket and will pass forwardly along the other edge ofthe cutter bar. Again, the chain elements will be captively held to theedge of the cutter bar by the inner action of their legs and th. wearstrips 8. The chain will be guided about the forward end of the cutterbar by suitable means such as the shoe 51 or an idler sprocket, asdescribed above.

FIG. 4 illustrates another embodiment of a cutter chain link member. Thelink member of FIG. 4 differs from the member 12 of FIGS. 2 and 3primarily in that it is made up of three pieces rather than being anintegral, one-piece unit. The link element of FIG. 4, generallyindicated at 54 is made up of a body member 55 and side members 56 and57. The body member 55 has a rounded forward end constituting asinglelink extension equivalent to the forward link extensions 14 and14b of FIGS. 2 and 3. The body member 55 also has a bottom surface (notshown) equivalent to the bottom surface 20 in FIG. 2. A shank-receivingperforation 58 and a transverse perforation 59 may also be provided inthe body member 55.

The side elements or members 56 and 57 are mirror images of each other.They have rearward extensions 60 and 61 equivalent to the space linkextensions 15 and 16 in FIG. 3. The extended portions 60 and 61 areprovided with coaxial perforations 62 and 63, respectively, for thereceipt of a pintle. The space between the extended portions 60 and 61is such as to receive the forward end of the body of an adjacent linkmember. Each of the side members 56 and 57 may have perforations (one ofwhich is shown at 64) which are coaxial with and comprise extensions ofthe transverse perforation 59 in the body member 55, for the receipt ofa resilient retaining means.

The side members 56 and 57 have downwardly depending portions 56a and57a, respectively, which are equivalent to the legs 21 and 22 of thelink member 12 of FIGS. 2, 3 and 7. The leg portions 56a and 57a haveinwardly turned portions 65 and 66 equivalent to the inward extensions23 and 24 of FIG. 7. The legs 56a and 57a are also provided withreliefs, three of which are shown at 67, 68 and 69. These reliefs areequivalent to those shown at 25 and 26 in FIG. 2. Finally, the sidemembers 56 and 57 have rearward surfaces 70 and 71 equivalent to thesurfaces 34 and 35 in FIGS. 2 and 3, as well as forward surfaces 72 and73 equivalent to the forward surfaces 36 and 37 in FIGS. 2 and 3.

The functioning of the link member of FIG. 4 will in every way, beidentical to the link members illustrated in FIGS. 2 and 3. The sidemembers 56 and 57 may be permanently or removably affixed to the bodymember 55 by any suitable means.

FIG. 9 is a cross-sectional view similar to FIGS. 7 and 8. In FIG. 9,the body portion 4 of the cutter bar 1 is shown carrying a link member,generally indicated at 74. The link member has a body portion 75 andlegs 76 and 77.

The link member 74 may be considered as being substantially identical tothe embodiment shown in FIGS. 2 and 3, or

' the embodiment shown in FIG. 4. The difference lies primarily in thefact that the legs 76 and 77 do not have inwardly extending leg portionsequivalent, for example, to those shown at 23 and 24 in FIGS. 7 and 8.For purposes of an exemplary showing, the peripheral edge of the cutterbar 1 is illustrated as not having wear strips. It will be understood byone skilled in the art that wear strips of any of the types describedabove could be applied in the same manner shown in FIGS. 7, 8 and 10.

FIG. 11 is a perspective view illustrating another embodiment of acutter chain of the present invention. A cutter-bitcarrying link memberis generally indicated at 78. The link member 78 has a body portion 79,a pair of legs 80 and 81 having inwardly turned portions 82 and 83respectively. The forward surfaces of the legs are relieved as at 84 and85. The rearward surfaces of the legs are similarly relieved (one suchrelief shown at 86).

Again, while the link member 78 may be adapted to carry any of theabove-discussed types of cutter bits or cutter bit adapted for purposesof an exemplary showing the link is illustrated as having ashank-receiving perforation 87 and a transverse perforation 88 for thereceipt of a resilient retaining means. As thus far described, theembodiment of FIG. 11 is generally similar to that of FIGS. 2 and 3. Theprimary difference lies in the fact that the link member 78 carries apair of spaced link extensions at both ends. The forward link extensionsare illustrated at 89 and 90, while the rearward extensions are shown at91 and 92. The forward extensions have coaxial perforations, one ofwhich is shown at 93. The rearward extensions have coaxial perforations94 and 95. It will be understood that the link member 78 could be aone-piece structure or could be made up of a number of pieces of thesame manner set forth with respect to FIG. 4.

Adjacent bit-carrying link s 7 8 are adapted to be joined by single-linkmembers, one of which is generally indicated at 96. The single-linkmember has perforations at each end (one of which is shown at 97). Theends of the single-link member 96 are adapted to nest between the spacedpairs of link extensions on adjacent bit-carrying link members and to bejoined thereto by pintle means passing through the coaxial perforationsin the space-link extensions and the perforations in the ends of thesingle-link members. An exemplary pintle is shown at 93a.

The above-described embodiment has several advantages. For example, whencompared to the embodiment of FIGS. 2 and 3, the cutter chain of FIG. 11will be seen to have twice as many joints. Thus, it is more flexible andthe pintles will remain nearer the peripheral edge of the guide means atthe forward end of the cutter bar as the chain passes thereabout.

Forces are at play in the embodiment of FIGS. 2 and 3 which will tend tomake the chain kick but these are compensated for by the arrangement ofthe chain members. For example, if the chain of FIG. 2 is moved in thedirection indicated by arrow C, the forward end of the link member 12will tend to rise in the direction of arrow D, while the rearward endwill tend to lower in the direction of arrow E. However, at the sametime, the rearward end of link member 12a will tend to lower in thedirection of arrow F while the forward end of link member 12b will tendto rise in the direction of arrow G. Thus, the opposite forces indicatedby arrows F and D and arrows E and G will tend to cancel each other andreduce the amount of kick displayed by the embodiment of FIG. 2. In anyof the em bodiments of the present invention wherein the cutter chainincludes single-link members of the type shown at 96 in FIG. 11, thechains will be more flexible and the pintles will ride nearer theperipheral edge of the forward guide means of the cutter bar.

FIGS. 12 and 13 illustrate yet another embodiment of the cutterbar-cutter chain of the present invention. In this embodiment, threeidentical links are illustrated at 98, 99 and 100. Each link member hasa single forward extension 98a, 99a and 100a. Similarly, each linkmember has a pair of spaced link extensions one each of which is shownat 93b, 99b and 10017. The various links are joined by pintle means 101,102 and 103.

As thus far described, the link members 98, 99 and 100 are substantiallysimilar to the link members 12, 12a and 12b of FIG. 2. Again the linkmembers may carry any suitable type of cutter bit or adapter andretaining means (not shown).

The cutter bar 104 may be of any suitable construction and has about itsperipheral edges a channel having an inverted T- shaped cross section.It will be understood by one skilled in the art that the channel couldhave a U-shaped cross section which could be modified to a T-shapedcross section by the placement of wear strips along the channel sides.One such wear strip is indicated in dotted lines at 106 in FIG. 13.Similarly, the bottom of the channel could be extended and provided witha wear strip, as indicated in dotted lines at 107.

The link members 98, 99 and I differ from those of FIGS. 2 and 3primarily in that each is provided with a single leg (108, 109 and 1rather than a pair of legs as shown in FIG. 2. Referring to FIG. 13, itwill be noted that the leg 108 has an inverted T-shaped configurationand is located centrally of the body of the link member 98. Thus, theconfiguration of the leg 108 and the configuration of the channel 105are such as to slidably but captively maintain the link element 98 inproper position with respect to the peripheral edges of the cutter bar104. The other legs I09 and 110 are similarly configured and similarlypositioned on the link members 99 and 100, respectively.

The forward and rearward edges of the legs I08, 109 and 110 are relievedas at 10811-1081, I09a-ll09b, and 11011-1 10b. These edges are adjustedto be engaged by sprocket means located in association with the rearwardend of the cutter bar. When a chain of the type shown in FIGS. 12 and 13is used, the forward end of the cutter bar will be provided withsuitable guide means as for example a shoe generally similar to thatshown in FIG. 10, but having a matching channel of inverted T-shapedcross section. When such a shoe is used, FIG. 13 could also beconsidered a cross-sectional view through the peripheral edge portion ofthe shoe.

In the embodiment of FIG. 12, it would be within the scope of theinvention to configure the double-link extensions 98b, 99b and 10Gb inthe same manner shown with respect to the double-link extensions in FIG.2, to rigidify the chain during its straight flights. Similarly, theforward faces of link members 98, 99 and 100 could be configured asshown in FIG. 1.

In like manner, it would be within the scope of the invention to provideeach of the link members 98, 99 and 100 with pairs of spaced linkextensions at both ends, as described with respect to FIG. II. In suchan instance, additional single-link members would be required.

This is illustrated in FIG. I4. A cutting-tool-carrying link member isgenerally shown at 111 having a body portion 112, forward linkextensions 113 and 114, and rearward link extensions 115 and I16. Thelink member 112 is provided with a single leg 117 similar to the legs108, 109 and 110 of FIG. 12. A single-link member is illustrated at 118,joined to the link member 1 11 by a pintle 119.

Suitable sprockets for driving the chains of FIGS. 12-14 are shown at150 and 152 in FIGS. 18 and 19.

FIGS. 15 and 16 illustrate yet another embodiment of the cutter chain ofthe present invention. A conventional drive sprocket is generallyindicated at 120. The sprocket has a plurality of spaced teeth 121 withintermediate peripheral edge portions 122 extending therebetween.

In FIG. 15, three identical link members 123-425 are shown passing aboutthe sprocket I20. For purposes of an exemplary showing, FIG. 16comprises a perspective view of link 124.

The link members of this embodiment are generally similar to those shownin FIGS. 1 and 2. The link 124 has a body portion 125 with a single-linkextension 126 at its forward end and a pair of spaced link extensionsI27 and 128 at its rearward end. The link extension 126 has apintle-receiving perforation 126a. Similarly the link extensions 127 andI28 have coaxial pintle-receiving perforations I27a and 128a. By virtueof this construction, the link elements l23-l25 can be joined togetherby pintle means 129 and 130. Again, the pintle means 129 and 130 may befreely rotatable in their respective pintle perforations and may extendbeyond the outside surfaces of the spaced link extension with means attheir ends for holding the pintles in place.

The body 125 of the link member 124 will have means (not shown) formounting a cutting tool of any suitable type.

The link member body 125 also has a pair of spaced legs I31 and 132substantially similar to the spaced legs illustrated in FIGS. 1 and 2.It is within the scope of the invention to provide the legs I31 and 132with inturned portions, one of which is illustrated at I33 in FIG. 15.These inturned leg portions will serve the same purpose as describedwith respect to the leg portions 23 and 24 in FIGS. 7 and 8.

The rearward edges of the spaced pair of link extensions 127 and 128 maybe planar as at 127b and 128b. The forward surfaces of the body 125 willalso be planar as at 134 and 135. The forward surfaces will also have aconcave portion, one of which is shown at 136. In this way, adjacentlink members will be free to pivot about their respective pintles asthey pass around the sprocket 120, but will be stabilized during theirstraight flights by the interaction of the rear edges of the spaced pairof link extensions of one link member and the straight portions of theforward edges of the adjacent link member. This interaction is similarto that described with respect to FIGS. I and 2.

The primary difference between the embodiment of FIGS. l5 and I6 and theembodiment of FIGS. I and 2 lies in the fact that the rear surface I250of the body portion 125 is spaced by a greater distance from the forwardlink extension of the adjacent link member. This permits entrancetherebetween of a sprocket tooth 121, as illustrated in FIG. 15. Thesprocket tooth may thus engage the surface 125a and drive the linkmember in a cutting direction. The bottom surfaces of the forward linkextension 126 and the body 125 are supported on a peripheral edgeportion 122 of the sprocket 120.

In all of the embodiments thus far described, it will be noted that thepintle means are located beyond the peripheral edges of the cutter bar.Thus, in all of the embodiments the ends of the pintle means are free toextend beyond the sides of the link members they join and thus thepintle means may be held in place by any of the various means describedwith respect to FIGS. 2, 3, and 6. It will be immediately evident thatthe distance between the point of contact between the tip of the cutterbit carried by the link members and the material being cut (i.e. thepoint of applied force) and the line of force passing through thepintles (i.e. the driving force) has been greatly reduced in eachembodiment. All of the assemblies thus far described will becharacterized by improved performance and longer service life.

FIG. 17 illustrates a modification of the cutter chain link elementswhich may be applied to any of the previously described embodiments.

The Figure illustrates two chain link elements 137 and 138. The linkelement 137 may have any suitable type of shankreceiving perforation asat 139. The link element may also have any of the leg means (not shown)described with respect to the previous embodiments.

A forward link extension is shown at 140 and a pair of rearward linkextensions is illustrated at 141 and 142. The link extensions 140-142are suitably perforated to accommodate pintle means.

The link element 138 is identical to link element 137 and has a forwardextension 143, rearward extensions 144 and 145 and a shank-receivingperforation 146.

In the structure of FIG. 17, it will be noted that the rearwardextensions 141-142 and 144-145 are suitably spaced to receivetherebetween the forward extension of an adjacent link member. Thisforward extension 143 is illustrated as being positioned betweenrearward extensions 141 and 142. A pintle 147 passes through coaxialperforations in link extensions 141, 142 and 143 effectively joininglink elements 137 and 138. In addition, however, the rearward extensions141-142 and 144-145 are spaced inwardly on the sides of their respectivelink elements 137 and 138. This enables the ends of pintle 147 to extendbeyond the outside surfaces of extensions 141 and 142 while at the sametime being protected by the body portions of the link elements 137 and138. Again, the pintle 147 may be freely rotatable and may be held inplace by any suitable means such as, for example, any of those taughtwith respect to FIGS. 2, 3, 5 and 6. For purposes of illustration, rollpins 30 are shown in FIG. 17.

FIG. is a fragmentary cross-sectional view similar to FIG. 7 andillustrates an advantage of the present invention. The cutter bar andwear strip members are the same as those in FIG. 7 and like parts havebeen given like index numerals. For purposes of an exemplaryillustration, a link member 153, similar to the link members 137 and 138of FIG. 17, is shown mounted on the cutter bar. The link member 153 hasleg portions 154 and 155 engaging and straddling the wear strips 7a and7b. The link member has a forward extension 156 carrying a pintle 157.Rearward extensions 158 and 159 of an adjacent link member are shown incross section.

The structure of the present invention enables the provision of a linkmember carrying two cutter bits in extreme cutting positions,substantially normal to the cutter bar. Bits 160 and 161 are shown inthese positions. The axes of the bits are coplanar. It will beunderstood by one skilled in the art that the link member 153 will beprovided with two transverse shank-receiving perforations, located onebehind the other.

Heretofore, when bits have been placed in these extreme positions, theblock or link member carrying them has been subjected to particularlysevere wear and has imparted severe wear to the cutter bar. This is truebecause the bits, by virtue of their positions, demonstrate both twistand kick.

In accordance with the present invention, however, it is possible tolocate the axes of the bits and 161 in substantially the same plane asthe axis of the pintle 157. The tendency for the block to twist isgreatly reduced by virtue of the fact that the bits 160 and 161 areoppositely disposed. The tendency for kick is substantially eliminatedby virtue of the fact that the applied force (i.e., the driving force onthe chain) passes through the axes of the bits and the axis of thepintle and is in line with the force applied to the bits by the materialbeing cut. Any of the link structures of the present invention may besubstituted for the one shown in FIG. 20 and will be characterized bythe same advantages.

Modifications may be made in the invention without departing from thespirit of it.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defied as follows:

1. A cutter bar, cutter chain and sprocket assembly for a mining machineand the like wherein said cutter bar comprises an elongated memberhaving longitudinal edge portions, a chain-driving sprocket inassociation with one end of said cutter bar and a chain guide meansaffixed to the other end of said cutter bar, an endless cutter chainextending along and supported by said longitudinal edge portions andextending about and supported by said sprocket and said guide means,said cutter chain comprising a plurality of link members some at leastof which carry cutting tools, certain ones at least of said link memberseach having a body and leg means projecting from said body, said legmeans engaging said longitudinal edge portions and said guide means,said link members being joined by pintles, said link members and saidpintles being positioned beyond said longitudinal edge portions of saidcutter bar and beyond the peripheral edges of said guide means, andengagement surfaces on some ofsaid link members to be drivingly engagedby said sprocket.

2. The structure claimed in claim 1 wherein each of said link memberswhich carries a cutting tool has said body, said body being adapted tomount a cutting tool, said body having a single-link extension at oneend and a pair of spaced link extensions at the other end, saidsingle-link extension having a transverse perforation therethrough, saidpair of link extensions having coaxial transverse perforationstherethrough, the single-link extension of each of said link membersbeing adapted to be received between the spaced pair of link extensionsof an adjacent link member with their respective perforations inalignment, and pintles passing through said aligned perforations ofadjacent link members to pivotally connect said adjacent link members.

3. The structure claimed in claim 1 wherein said cutter chain comprisesa plurality of cutting-tool-carrying link members connected together byalternate single-link members, each of said cutting-tool-carrying linkmembers having a body portion with a pair of spaced link extensions atboth ends, the spaced link extensions of each pair having coaxialtransverse perforations therethrough, said single-link members eachhaving a transverse perforation at both ends thereof, the ends of eachsingle-link member being adapted to be received between a pair of spacedlink extensions of two adjacent cutting-tool-carrying link members withtheir respective transverse perforations being in alignment, saidpintles passing through said aligned perforations.

4. The structure claimed in claim 1 wherein said leg means comprises aleg of inverted T-shaped cross section, said cutter bar having channelsin its longitudinal edge portions, each of said channels having anchannels having an inverted T-shaped cross section, said legs of saidlink members having a sliding fit in said channels.

5. The structure claimed in claim 1 wherein said leg means comprises aleg of inverted T-shaped cross section, said cutter bar having channelsin its longitudinal edge portions, each of said channels having aU-shaped cross section, wear strips affixed to the sidewalls of saidchannels giving said channels inverted T-shaped cross sections, saidlegs of said link members having a sliding fit in said channels equippedwith said wear strips.

6. The structure claimed in claim 1 wherein said leg means comprises apair of spaced legs, said pairs of spaced legs being configured tostraddle and slidably engage said longitudinal edge portions of saidcutter bar.

7. The structure claimed in claim 2 wherein said pintles are freelyrotatable in their respective aligned perforations, end portions of eachof said pintles extending beyond the exterior surfaces of the spacedpair of link extensions through which it passes, means in associationwith said end portions of said pintles for maintaining said pintles insaid aligned perforations through which they pass.

8. The structure claimed in claim 2 wherein said leg means comprises apair of spaced legs, said pair of spaced legs being configured tostraddle and slidably engage said longitudinal edge portions of saidcutter bar, said drive sprocket having a peripheral edge with aplurality of spaced teeth, each of said link members adapted to passabout said sprocket with its pair of legs stradling said peripheral edgeof said sprocket between said teeth, and said engagement surfacescomprising the rear surfaces of the link member body portions which areengaged by one of said teeth, said last-mentioned tooth being locatedbetween said pair of link extensions on said link member body portionahead of the single-link extension of the adjacent link member.

9. The structure claimed in claim 3 wherein said pintles are freelyrotatable in their respective aligned perforations, end portions of eachof said pintles extending beyond the exterior surfaces of the spacedpair of link extensions through which it passes, means in associationwith said end portions of said pintles for maintaining said pintles insaid aligned perforations through which they pass.

10. The structure claimed in claim 4 wherein said guide means comprisesa member having a peripheral edge a portion at least of which issubstantially semicircular, said peripheral edge having a channeltherein of inverted T-shaped cross section comprising a continuation ofsaid channels in said cutter bar, said legs of said link members havinga sliding fit in said guide means channel.

11. The structure claimed in claim 5 wherein said guide means comprisesa member having a peripheral edge a portion at least of which issubstantially semicircular, said peripheral edge having a channeltherein of U-shaped cross section, wear strips affixed to the sidewallsof said guide means channel giving said channel an inverted T-shapedcross section, said guide means channel and said guide means wear stripscomprising a continuation of said channels and wear strips of saidcutter bar, said legs of said link members having a sliding fit in saidguide means channel equipped with said guide means wear strips.

12. The structure claimed in claim 6 wherein said cutter bar has wearstrip means along both sides of each of said longitudinal edge portions,the free ends of each-of said pairs of link member legs being inturnedtoward each other, said pairs of spaced legs being configured tostraddle said wear strip means and to be slidably hooked thereabout.

13. The structure claimed in claim 6 wherein said drive sprocketcomprises a disk like body having two faces and a peripheral edge, saidsprocket having a plurality of lugs on at least one of said faces nearsaid peripheral edge and extending transversely thereof, said cutterchain passing about said sprocket with said link member legs straddlingthe peripheral portion of said sprocket body, said engagement surfacesbeing located on said legs and engaged by said lugs.

14. The structure claimed in claim 6 wherein said guide means comprisesa member having a peripheral edge a portion at least of which issubstantially semicircular, said peripheral edge comprising acontinuation of said longitudinal edge portions of said cutter bar, saidpairs of link member legs being configured to straddle and engage saidperipheral edge of said guide means.

15. The structure claimed in claim 6 wherein said guide means comprisesan idler sprocket affixed to the forward end of said cutter bar, saidsprocket comprising a body portion having two faces and a peripheraledge, said sprocket having a plurality of lugs on at least one of itssaid faces near said peripheral edge, said cutter chain passing aboutsaid sprocket with said link member legs straddling the peripheralportion of said sprocket body and located between adjacent ones of saidlugs, said engagement surfaces being located on said legs and engaged bysaid lugs.

16. The structure claimed in claim 12 wherein said guide means comprisesa member having a peripheral edge a portion at leastof which issubstantially semicircular, said peripheral edge of said guide meanscomprising a continuation of the longitudinal edge portions of saidcutter bar, said peripheral edge of said guide means having wear stripmeans on both sides thereof comprising continuations of said wear stripson said cutter bar, said pairs of link member legs being configured tostraddle said wear strip means on said guide means and to be slidablyhooked thereabout.

17. A sprocket for engaging the cutter chain of a mining machine or thelike, comprising a rotatable disk like body havingtwo faces and aperipheral edge, said sprocket having a plurality of lugs on at leastone of said faces near said peripheral edge and extending transverselythereof.

18. A cutter bar for a mining machine and the like comprising anelongated member having a top and a bottom surface and longitudinal edgesurfaces, each of said longitudinal edge surfaces being planar, normalto said top and bottom surfaces and extending from said top to saidbottom surface.

19. The structure claimed in claim 18 including wear strips affixed tosaid top and bottom surfaces adjacent said longitudinal edge surfaces.

20. A link member for a cutter chain and the like comprising a bodyportion adapted to mount a cutting tool, said body having a single-linkextension at one end and a pair of spaced link extensions at the otherend, said single-link extension having a transverse perforationtherethrough, said pair of link extensions having coaxial transverseperforations therethrough, said single-link extension and said pair oflink extensions being so configured that the single-link extension ofone such link element may be received between the pair of linkextensions of another such link element with said perforations in saidsingle and said pair of link extensions being coaxial, said body portionhaving at least one leg projecting therefrom adapted to slidably engagethe longitudinal edge portions of a cutter bar.

21. The structure claimed in claim 20 wherein said body portion has aleg of inverted T-shaped cross section adapted to slidably engagechannels of inverted T-shaped cross section in the longitudinal edgeportions of a cutter boar.

22. The structure claimed in claim 20 wherein said body portion has apair of spaced legs extending therefrom, said pair of spaced legs beingconfigured to straddle and slidably engage the longitudinal edgeportions of a cutter bar.

23. The structure claimed in claim 22 wherein said pair of spaced linkextensions are of sufficient length to permit the tooth of a sprocket toenter therebetween and engage the rear surface of said body portionahead of the single link extension of the adjacent link member.

24. The structure claimed in claim 22 wherein the free ends of saidspaced legs are turned inwardly, and said inturned ends adapted to beslidably hooked about wear strips on the longitudinal edge portions of acutter bar.

25. A link member for a cutter chain and the like comprising a bodyportion having a pair of spaced link extensions at both ends, the spacedlink extensions of each pair having coaxial transverse perforationstherethrough, said link member adapted to be connected to a similar linkmember by a single-link member having perforated ends adapted to bereceived between adjacent pairs of spaced link extensions with saidperforations in said nested parts being coaxial, said body portion ofsaid link member having at least one leg adapted to slidably engage thelongitudinal edge portions of a cutter bar.

26. The structure claimed in claim 25 wherein said body portion has aleg of inverted T-shaped cross section adapted to slidably engagechannels of inverted T-shaped cross section in the longitudinal edgeportions of a cutter bar.

27. The structure claimed in claim 25 wherein said body portion has apair of spaced legs extending therefrom, said pair of spaced legs beingconfigured to straddle and slidably engage the longitudinal edgeportions of a cutter bar.

28. A cutter chain for a mining machine and the like comprising aplurality of link members joined by pintles, each of said link membershaving a body adapted to mount a cutting tool, said body having asingle-link extension at one end and a pair of spaced link extensions atthe other end, said single-link extensions having a transverseperforation therethrough, said pair of link extensions having coaxialtransverse perforations therethrough, the single-link extension of eachof said link members being located between the spaced pair of linkextensions of an adjacent link member with their respective perforationsin alignment, said pintles passing through said aligned perforations ofadjacent link members to pivotally connect said adjacent link members,the ends of said pintles extending beyond the exterior surfaces of saidpairs of spaced link extensions, means in association with said ends ofsaid pintles, to hold said pintles in place, each of said pintles beingfreely rotatable within its respective coaxial perforations, each ofsaid link members having at least one leg projecting from said body andadapted to slidably engage the edge portions of a cutter bar.

29. The structure claimed in claim 28 wherein said pair of spaced linkextensions of each link member is of sufficient length to permitentrance therebetween of one of the teeth of a drive sprocket andengagement by said tooth of the rear surface of the body portion of saidlink member ahead of the single-link extension of theadjacent linkmember.

30. A cutter chain for a mining machine and the like said cutter chaincomprising a plurality of cutting-tool-carrying members connectedtogether by alternate single-link members, each of saidcutting-tool-carrying link members having a body portion with a pair ofspaced link extensions at both ends, the spaced link extensions of eachpair having coaxial transverse perforations therethrough, saidsingle-link members each having a transverse perforation at both endsthereof, the ends of each single-link member being adapted to bereceived between a pair of double-link extensions of two adjacentcutting-tool-carrying link members with their respective transverseperforations being in alignment, said pintles passing through saidaligned perforations and being freely rotatable therein, the ends ofsaid pintles extending beyond the exterior surfaces of said pairs ofspaced link extensions, means in association with said ends of saidpintles to hold said pintles in place in their respective coaxialperforations, each of said cutting-tool-carrying link members having atleast one leg to slidably engage the edge portions of a cutter bar.

31. A cutter chain for use with a cutter bar and sprocket assembly andthe like, said cutter chain being comprised of a plurality of linkmembers, pintles for joining adjacent link members, certain of said linkmembers at least having leg means to engage a chain guide surface on theperiphery of the cutter bar, and said pintles being located outside ofthe periphery of the cutter bar chain guide surface when said chain ismounted on the cutter bar, at least some of said link members beingadapted to receive cutter bits which extend away from the chain guidesurface.

32. The cutter chain of claim 31 in which said leg means comprises apair of members adapted to straddle the chain guide surface.

33. The cutter chain of claim 31 in which said leg means comprises agenerally T-shaped member adapted to engage a similarly shaped channelconstituting a part of the chain guide surface.

34. The cutter chain of claim 31 in which said pintles are freelyrotatable with respect to said link members.

35. The cutter chain of claim 31 in which the ends of said pintlesextend beyond the surfaces of the link members they join. 36. The cutterchain ofclaim 31 in which said leg means are provided with surfaces tobeengaged by the sprocket,

37. An assembly including a cutter bar, a chain and a sprocket, saidchain being comprised of a plurality of link members, said cutter barhaving a chain guide surface at its periphery, certain at least of saidlink members having leg means to engage said chain guide surface,pintles engaging adjacent link members, said pintles being locatedbeyond the chain guide surface, some of said link members being adaptedto receive cutter bits, and engagement surfaces on some of said linkmembers to be engaged by said sprocket.

38. The assembly of claim 1 including chain guide surfaces on saidlongitudinal edge portions, said leg means engaging said chain guidesurfaces, and said pintles being beyond said chain guide surfaces.

39. The assembly of claim 37 wherein said leg means comprises adepending member having at least one lateral extension, and said cutterbar chain guide surface comprising a channel in the longitudinal edgeportion of said cutter bar, said channel having a configuration whichconforms with said leg means, said leg means having a sliding fit insaid channel.

40. The assembly of claim 39 including a chain guide means fixed at oneend of said cutter bar, said chain guide means comprising a memberhaving a peripheral edge a portion at least of which is substantiallysemicircular, said peripheral edge having a channel therein of aconfiguration which comprises a continuation of said channel in saidcutter bar, said leg means also having a sliding fit in said chain guidemeans channel.

41. The sprocket of claim 17 in which said body is provided with arelief in said peripheral edge between each of said lugs.

42. The cutter bar of claim 18 in which said cutter bar is designed toreceive a chain comprised of a plurality of link members joined bypintles, some at least of said link members having leg means to engagesaid cutter bar, the thickness of said cutter bar being less than thethickness of said link members.

43. The link member of claim 20 in which said pair of spaced linkextensions is set inwardly from the lateral sides of said link membersufficient that a pintle may be passed through said coaxial perforationswhereby to join said pair of link extensions with a said single-linkextension with the ends of said pintle stopping short of or at thelateral sides of said link member.

44. The cutter chain of claim 31 in which said leg means comprises adepending member having at least one lateral extension, and said cutterbar chain guide surface comprising a channel on the periphery of saidcutter bar, said channel having a configuration which conforms with saidleg means, said leg means having a sliding fit in said channel.

45. The link member of claim 20 including a pair of cutting toolsmounted on said body portion, the axes of said cutting tools beingsubstantially coplanar and substantially normal to the cutter bar, saidcutting tools being disposed about l from one another and each extendingoutwardly from said body portion, the axes of said cutting tools beingin substantially the same plane as the said coaxial perforations in thesaid pair of spaced link extensions.

46. The assembly of claim 37 in which a said link member adapted toreceive cutter bits is provided with a pair of cutter bits, the axes ofsaid cutter bits being substantially coplanar and substantially normalto said cutter bar, said cutter bits being disposed about from oneanother and each extending outwardly from said link member, the axes ofsaid cutter bits and the axes of said pintles being in substantially thesame plane.

1. A cutter bar, cutter chain and sprocket assembly for a mining machineand the like wherein said cutter bar comprises an elongated memberhaving longitudinal edge portions, a chaindriving sprocket inassociation with one end of said cutter bar and a chain guide meansaffixed to the other end of said cutter bar, an endless cutter chainextending along and supported by said longitudinal edge portions andextending about and supported by said sprocket and said guide means,said cutter chain comprising a plurality of link members some at leastof which carry cutting tools, certain ones at least of said link memberseach having a body and leg means projecting from said body, said legmeans engaging said longitudinal edge portions and said guide means,said link members being joined by pintles, said link members and saidpintles being positioned beyond said longitudinal edge portions of saidcutter bar and beyond the peripheral edges of said guide means, andengagement surfaces on some of said link members to be drivingly engagedby said sprocket.
 2. The structure claimed in claim 1 wherein each ofsaid link members which carries a cutting tool has said body, said bodybeing adapted to mount a cutting tool, said body having a single-linkextension at one end and a pair of spaced link extensions at the otherend, said single-link extension having a transverse perforationtherethrough, said pair of link extensions having coaxial transverseperforations therethrough, the single-link extension of each of saidlink members being adapted to be received between the spaced pair oflink extensions of an adjacent link member with their respectiveperforations in alignment, and pintles passing through said alignedperforations of adjacent link members to pivotally connect said adjacentlink members.
 3. The structure claimed in claim 1 wherein said cutterchain comprises a plurality of cutting-tool-carrying link membersconnected together by alternate single-link members, each of saidcutting-tool-carrying link members having a body portion with a pair ofspaced link extensions at both ends, the spaced link extensions of eachpair having coaxial transverse perforations therethrough, saidsingle-link members each having a transverse perforation at both endsthereof, the ends of each single-link member being adapted to bereceived between a pair of spaced link extensions of two adjacentcutting-tool-carrying link members with their respective transverseperforations being in alignment, said pintles passing through saidaligned perforations.
 4. The structure claimed in claim 1 wherein saidleg means comprises a leg of inverted T-shaped cross section, saidcutter bar having channels in its longitudinal edge portions, each ofsaid channels having an channels having an inverted T-shaped crosssection, said legs of saId link members having a sliding fit in saidchannels.
 5. The structure claimed in claim 1 wherein said leg meanscomprises a leg of inverted T-shaped cross section, said cutter barhaving channels in its longitudinal edge portions, each of said channelshaving a U-shaped cross section, wear strips affixed to the sidewalls ofsaid channels giving said channels inverted T-shaped cross sections,said legs of said link members having a sliding fit in said channelsequipped with said wear strips.
 6. The structure claimed in claim 1wherein said leg means comprises a pair of spaced legs, said pairs ofspaced legs being configured to straddle and slidably engage saidlongitudinal edge portions of said cutter bar.
 7. The structure claimedin claim 2 wherein said pintles are freely rotatable in their respectivealigned perforations, end portions of each of said pintles extendingbeyond the exterior surfaces of the spaced pair of link extensionsthrough which it passes, means in association with said end portions ofsaid pintles for maintaining said pintles in said aligned perforationsthrough which they pass.
 8. The structure claimed in claim 2 whereinsaid leg means comprises a pair of spaced legs, said pair of spaced legsbeing configured to straddle and slidably engage said longitudinal edgeportions of said cutter bar, said drive sprocket having a peripheraledge with a plurality of spaced teeth, each of said link members adaptedto pass about said sprocket with its pair of legs stradling saidperipheral edge of said sprocket between said teeth, and said engagementsurfaces comprising the rear surfaces of the link member body portionswhich are engaged by one of said teeth, said last-mentioned tooth beinglocated between said pair of link extensions on said link member bodyportion ahead of the single-link extension of the adjacent link member.9. The structure claimed in claim 3 wherein said pintles are freelyrotatable in their respective aligned perforations, end portions of eachof said pintles extending beyond the exterior surfaces of the spacedpair of link extensions through which it passes, means in associationwith said end portions of said pintles for maintaining said pintles insaid aligned perforations through which they pass.
 10. The structureclaimed in claim 4 wherein said guide means comprises a member having aperipheral edge a portion at least of which is substantiallysemicircular, said peripheral edge having a channel therein of invertedT-shaped cross section comprising a continuation of said channels insaid cutter bar, said legs of said link members having a sliding fit insaid guide means channel.
 11. The structure claimed in claim 5 whereinsaid guide means comprises a member having a peripheral edge a portionat least of which is substantially semicircular, said peripheral edgehaving a channel therein of U-shaped cross section, wear strips affixedto the sidewalls of said guide means channel giving said channel aninverted T-shaped cross section, said guide means channel and said guidemeans wear strips comprising a continuation of said channels and wearstrips of said cutter bar, said legs of said link members having asliding fit in said guide means channel equipped with said guide meanswear strips.
 12. The structure claimed in claim 6 wherein said cutterbar has wear strip means along both sides of each of said longitudinaledge portions, the free ends of each of said pairs of link member legsbeing inturned toward each other, said pairs of spaced legs beingconfigured to straddle said wear strip means and to be slidably hookedthereabout.
 13. The structure claimed in claim 6 wherein said drivesprocket comprises a disk like body having two faces and a peripheraledge, said sprocket having a plurality of lugs on at least one of saidfaces near said peripheral edge and extending transversely thereof, saidcutter chain passing about said sprocket with said link member legsstraddling the peripheral portion of said sproCket body, said engagementsurfaces being located on said legs and engaged by said lugs.
 14. Thestructure claimed in claim 6 wherein said guide means comprises a memberhaving a peripheral edge a portion at least of which is substantiallysemicircular, said peripheral edge comprising a continuation of saidlongitudinal edge portions of said cutter bar, said pairs of link memberlegs being configured to straddle and engage said peripheral edge ofsaid guide means.
 15. The structure claimed in claim 6 wherein saidguide means comprises an idler sprocket affixed to the forward end ofsaid cutter bar, said sprocket comprising a body portion having twofaces and a peripheral edge, said sprocket having a plurality of lugs onat least one of its said faces near said peripheral edge, said cutterchain passing about said sprocket with said link member legs straddlingthe peripheral portion of said sprocket body and located betweenadjacent ones of said lugs, said engagement surfaces being located onsaid legs and engaged by said lugs.
 16. The structure claimed in claim12 wherein said guide means comprises a member having a peripheral edgea portion at least of which is substantially semicircular, saidperipheral edge of said guide means comprising a continuation of thelongitudinal edge portions of said cutter bar, said peripheral edge ofsaid guide means having wear strip means on both sides thereofcomprising continuations of said wear strips on said cutter bar, saidpairs of link member legs being configured to straddle said wear stripmeans on said guide means and to be slidably hooked thereabout.
 17. Asprocket for engaging the cutter chain of a mining machine or the like,comprising a rotatable disk like body having two faces and a peripheraledge, said sprocket having a plurality of lugs on at least one of saidfaces near said peripheral edge and extending transversely thereof. 18.A cutter bar for a mining machine and the like comprising an elongatedmember having a top and a bottom surface and longitudinal edge surfaces,each of said longitudinal edge surfaces being planar, normal to said topand bottom surfaces and extending from said top to said bottom surface.19. The structure claimed in claim 18 including wear strips affixed tosaid top and bottom surfaces adjacent said longitudinal edge surfaces.20. A link member for a cutter chain and the like comprising a bodyportion adapted to mount a cutting tool, said body having a single-linkextension at one end and a pair of spaced link extensions at the otherend, said single-link extension having a transverse perforationtherethrough, said pair of link extensions having coaxial transverseperforations therethrough, said single-link extension and said pair oflink extensions being so configured that the single-link extension ofone such link element may be received between the pair of linkextensions of another such link element with said perforations in saidsingle and said pair of link extensions being coaxial, said body portionhaving at least one leg projecting therefrom adapted to slidably engagethe longitudinal edge portions of a cutter bar.
 21. The structureclaimed in claim 20 wherein said body portion has a leg of invertedT-shaped cross section adapted to slidably engage channels of invertedT-shaped cross section in the longitudinal edge portions of a cutterboar.
 22. The structure claimed in claim 20 wherein said body portionhas a pair of spaced legs extending therefrom, said pair of spaced legsbeing configured to straddle and slidably engage the longitudinal edgeportions of a cutter bar.
 23. The structure claimed in claim 22 whereinsaid pair of spaced link extensions are of sufficient length to permitthe tooth of a sprocket to enter therebetween and engage the rearsurface of said body portion ahead of the single link extension of theadjacent link member.
 24. The structure claimed in claim 22 wherein thefree ends of said spaced legs are turned inwardly, and said intUrnedends adapted to be slidably hooked about wear strips on the longitudinaledge portions of a cutter bar.
 25. A link member for a cutter chain andthe like comprising a body portion having a pair of spaced linkextensions at both ends, the spaced link extensions of each pair havingcoaxial transverse perforations therethrough, said link member adaptedto be connected to a similar link member by a single-link member havingperforated ends adapted to be received between adjacent pairs of spacedlink extensions with said perforations in said nested parts beingcoaxial, said body portion of said link member having at least one legadapted to slidably engage the longitudinal edge portions of a cutterbar.
 26. The structure claimed in claim 25 wherein said body portion hasa leg of inverted T-shaped cross section adapted to slidably engagechannels of inverted T-shaped cross section in the longitudinal edgeportions of a cutter bar.
 27. The structure claimed in claim 25 whereinsaid body portion has a pair of spaced legs extending therefrom, saidpair of spaced legs being configured to straddle and slidably engage thelongitudinal edge portions of a cutter bar.
 28. A cutter chain for amining machine and the like comprising a plurality of link membersjoined by pintles, each of said link members having a body adapted tomount a cutting tool, said body having a single-link extension at oneend and a pair of spaced link extensions at the other end, saidsingle-link extensions having a transverse perforation therethrough,said pair of link extensions having coaxial transverse perforationstherethrough, the single-link extension of each of said link membersbeing located between the spaced pair of link extensions of an adjacentlink member with their respective perforations in alignment, saidpintles passing through said aligned perforations of adjacent linkmembers to pivotally connect said adjacent link members, the ends ofsaid pintles extending beyond the exterior surfaces of said pairs ofspaced link extensions, means in association with said ends of saidpintles, to hold said pintles in place, each of said pintles beingfreely rotatable within its respective coaxial perforations, each ofsaid link members having at least one leg projecting from said body andadapted to slidably engage the edge portions of a cutter bar.
 29. Thestructure claimed in claim 28 wherein said pair of spaced linkextensions of each link member is of sufficient length to permitentrance therebetween of one of the teeth of a drive sprocket andengagement by said tooth of the rear surface of the body portion of saidlink member ahead of the single-link extension of the adjacent linkmember.
 30. A cutter chain for a mining machine and the like said cutterchain comprising a plurality of cutting-tool-carrying members connectedtogether by alternate single-link members, each of saidcutting-tool-carrying link members having a body portion with a pair ofspaced link extensions at both ends, the spaced link extensions of eachpair having coaxial transverse perforations therethrough, saidsingle-link members each having a transverse perforation at both endsthereof, the ends of each single-link member being adapted to bereceived between a pair of double-link extensions of two adjacentcutting-tool-carrying link members with their respective transverseperforations being in alignment, said pintles passing through saidaligned perforations and being freely rotatable therein, the ends ofsaid pintles extending beyond the exterior surfaces of said pairs ofspaced link extensions, means in association with said ends of saidpintles to hold said pintles in place in their respective coaxialperforations, each of said cutting-tool-carrying link members having atleast one leg to slidably engage the edge portions of a cutter bar. 31.A cutter chain for use with a cutter bar and sprocket assembly and thelike, said cutter chain being comprised of a plurality of link members,pintles for joiniNg adjacent link members, certain of said link membersat least having leg means to engage a chain guide surface on theperiphery of the cutter bar, and said pintles being located outside ofthe periphery of the cutter bar chain guide surface when said chain ismounted on the cutter bar, at least some of said link members beingadapted to receive cutter bits which extend away from the chain guidesurface.
 32. The cutter chain of claim 31 in which said leg meanscomprises a pair of members adapted to straddle the chain guide surface.33. The cutter chain of claim 31 in which said leg means comprises agenerally T-shaped member adapted to engage a similarly shaped channelconstituting a part of the chain guide surface.
 34. The cutter chain ofclaim 31 in which said pintles are freely rotatable with respect to saidlink members.
 35. The cutter chain of claim 31 in which the ends of saidpintles extend beyond the surfaces of the link members they join. 36.The cutter chain of claim 31 in which said leg means are provided withsurfaces to be engaged by the sprocket.
 37. An assembly including acutter bar, a chain and a sprocket, said chain being comprised of aplurality of link members, said cutter bar having a chain guide surfaceat its periphery, certain at least of said link members having leg meansto engage said chain guide surface, pintles engaging adjacent linkmembers, said pintles being located beyond the chain guide surface, someof said link members being adapted to receive cutter bits, andengagement surfaces on some of said link members to be engaged by saidsprocket.
 38. The assembly of claim 1 including chain guide surfaces onsaid longitudinal edge portions, said leg means engaging said chainguide surfaces, and said pintles being beyond said chain guide surfaces.39. The assembly of claim 37 wherein said leg means comprises adepending member having at least one lateral extension, and said cutterbar chain guide surface comprising a channel in the longitudinal edgeportion of said cutter bar, said channel having a configuration whichconforms with said leg means, said leg means having a sliding fit insaid channel.
 40. The assembly of claim 39 including a chain guide meansfixed at one end of said cutter bar, said chain guide means comprising amember having a peripheral edge a portion at least of which issubstantially semicircular, said peripheral edge having a channeltherein of a configuration which comprises a continuation of saidchannel in said cutter bar, said leg means also having a sliding fit insaid chain guide means channel.
 41. The sprocket of claim 17 in whichsaid body is provided with a relief in said peripheral edge between eachof said lugs.
 42. The cutter bar of claim 18 in which said cutter bar isdesigned to receive a chain comprised of a plurality of link membersjoined by pintles, some at least of said link members having leg meansto engage said cutter bar, the thickness of said cutter bar being lessthan the thickness of said link members.
 43. The link member of claim 20in which said pair of spaced link extensions is set inwardly from thelateral sides of said link member sufficient that a pintle may be passedthrough said coaxial perforations whereby to join said pair of linkextensions with a said single-link extension with the ends of saidpintle stopping short of or at the lateral sides of said link member.44. The cutter chain of claim 31 in which said leg means comprises adepending member having at least one lateral extension, and said cutterbar chain guide surface comprising a channel on the periphery of saidcutter bar, said channel having a configuration which conforms with saidleg means, said leg means having a sliding fit in said channel.
 45. Thelink member of claim 20 including a pair of cutting tools mounted onsaid body portion, the axes of said cutting tools being substantiallycoplanar and substantially normal to the cutter bar, said cutting toolsbeing disposed about 180* from one another and each extending outwardlyfrom said body portion, the axes of said cutting tools being insubstantially the same plane as the said coaxial perforations in thesaid pair of spaced link extensions.
 46. The assembly of claim 37 inwhich a said link member adapted to receive cutter bits is provided witha pair of cutter bits, the axes of said cutter bits being substantiallycoplanar and substantially normal to said cutter bar, said cutter bitsbeing disposed about 180* from one another and each extending outwardlyfrom said link member, the axes of said cutter bits and the axes of saidpintles being in substantially the same plane.